Vacuum cleaner



. 5, 1939. c. E. LoFGREN VACUUM CLEANER Filed April 23, 1936 4 Sheets-Sheet 1 hm, Y//Q QO O O OO M4 A. ATTORNEY.

G. E. LOFGREN VACUUM CLEANER Dec. 5, 1939.

Filed April 23. 1956 4 Sheets-Sheet 2 am H 0000 co2: Q

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Dec. s, 1939. Y G, E, OFGREN 2,182,343

VACUUM CLEANER Filed April7 23, 1936 4 Sheets-Sheet 3 h ef 1Nv NTOR,

/ ATTORNEY.

5', 1939. G, E, LOFGREN 2,182,343

VACUUM CLEANER Filed April 23, 1936 4 Sheets-#Sheet 4 J .u ATTORNEY.

F I BY 7 9' Patented Dec. 5, 1939 UNITED STATES PATENT OFFICE VACUUM CLEANER Gustaf Einar Lofgren, Riverside, Conn., assignor to Electrolux Corporation, Dover, Del., a corporation of Delaware Application April 23, 1936, Serial No. 75,954

16 Claims.

. tains a dust separating member and a fan, with a cleaning tool. During normal operation of the device, air is drawn in through the cleaning tool and the conduit, is passed through the dust separating member for the removal of entrained dust and is discharged in puried state into the atmosphere. In order to reduce the back pressure as far as possible, it is desirable to provide an exhaust opening or openings having as large a cross-section as possible. It is also desirable that the exhaust opening or openings deliver the air in a direction away from thesurface von which the Cleanerunit is supported in order that this air will not agitate any dust which may be on the surface...

At times it may be wishedto use the cleaner lunit as ablowerv and to connect the air conduit or hosefto anrexhaust opening so that vthe air' may bereadily deliveredto a Vdesired point of use.

In accordance with my'invention, there isprovideda. vacuum cleaner-*unit having a plurality 'lof ,exhaustopenings. One; of these openings is 'arranged for the connectiontherewith o f an air 'conduit y Valve means are provided operable upon the connecting of the hose to automatically cut oif. ow of air through the remaining exhaust openings.. The exhaust openings to which the hose .isconnectible is preferably arranged inv a substantially 4horizontal plane in order that when the hose is connected it may extend from the cleaner in a substantially horizontal direction,

and air vanes are provided for directing the air upwardly and away from the supporting surface when the 'air conduit is,.-notconnected. These vanesare advantageously rformed as a part of theaforesaid valve means and are displaceable `along with the valve means when the hose is connected. preferably located in a part of the casing which is so curved that the air discharged therethrough is directed away from the supporting surface.

Another object of my invention isto provide a filtering 'member advantageously arranged in conjunction with the plurality of exhaust openings so that all of the air exhausted from the cleaner unit must pass through the lter. My invention also contemplates locating the exhaust The remaining exhaust openings arev openings and the aforesaid valve means in an end-piece which may be removably secured to the main portion of the cleaner casing by means of a member which is accessible for manipulation through one'of the exhaust openings. Preferably 5 this means includes a bolt disposed Within the exhaust opening to which the air conduit may be connected and extending flush with the outer surface of the air vanes carried by the valve means. This bolt may be made accessible for l( manipulation by displacing the vanes and valve means in a manner similar to that in which they are displaced when the hose is connected. Further, my invention contemplates arranging the aforesaid filter member so that the fastening of l5 the end-piece to the main housing secures it in place. l

Further objects and advantages of my invention will be apparent from thefollowing descrip-v tion considered in connection with the accom-y ,20. panying drawings, which form a part of the spec- Y iiication andoffwhich:-

Fig. 1 is a side-view,partially in ment of my nventiom- .l Fig.-2 is a rear view ona somewhat reduced scale ofthe device sh'own in-;Fig.f-'1; 1

Fig-3' is a. crossfsectional view fon an-enlarge scale Aand-is taken on thewlines 3-.`3 o Figs :'1

Fig; 4 is a cross-sectional view,E on an'fenlarg scale taken on the line 4 4 of Fi g.12; '.1

Fig. 5 is a cross-sectional,view taken line 5-5 ofFig.4; I

Fig. 6 is a cross-sectional viewof aportion offgzfiv i.,

the device iuustrated in Fig. i but with anyair conduit connected thereto;

Fig. 7 is a cross-sectional view takenon theline n 1--1 of Fig. 6;

Fig. a is a cross-sectional view similar to Fig. 4 A4Q;`

but showing another embodiment of my invention;

Fig. 10 is a cross-sectional view taken v ontheline--415 y embodiment of my invention;

'cross-section; g of a vacuum cleaner unit includingl one embodiwith?? Fig. 9 is a cross-sectional view taken on the line similar to Fig. 5

Fig. 13 is a cross-sectional view of a'fourth Fig. v14 is a cross-sectional view taken on the line I4-I4 of Fig. 13; and

Fig. 15 is a cross-sectional view taken on the line I5-I5 of Fig.'13.

Referring more particularly to the device shown in Figs. 1 through '7, reference character 'I8 designates generally a casing of a vacuum cleaner unit. Casing I0 includes the main casing member II which may preferably comprise sheet metal stampings forming a hollow elongated body more or lless open at each end. One end of member II may be closed by means of a front cover I2 which may be removably secured to member II by any suitable means. Cover I2 is provided with an opening I3 adapted to receive a coupling member I4 secured to one end of a flexible hose or air conduit I5. The other end of hose I5 may be connected with a suction nozzle I6 by means of a hollow rigid handle member I1.

A dust separating member 20 in the form of a bag having its open mouth secured to a anged ring 2| is disposed Within casing member II. The

`iiange of ring 2| is adapted to be clamped between the casing member II and the front cover I 2 when the latter is secured in place. Dust separatingmember 20 is made of suitable material such as cloth which is pervious with respect to air, but impervious with respect to dust.

A pair of spaced bulkheads 22 and 23 are disposed within casing member i I and divide the interior thereof into a dust bag compartment 24, a motor-fan compartment 25. and a filter compartment 26. A motor fan unit, including an electric motor 21 and a centrifugal fan 28 mounted within an air-tight casing 29, is disposed within motor-fan compartment 25 and is supported between bulkheads 22 and 23 by air-tight sealing rings 30 and 3| which engage Within openings formed in the respective bulkheads and in the opposite ends of casing 29.

Filter space 26 is bounded in part by a portion of casing member II and in part by an endpiece 34, which may be in the form of a casting. In the embodiment shown in Figs. 1 through '1, casting 34 is secured to the main casing member II by means of screws 35. Casting 34 is formed with a cylindrical exhaust opening 36 having asubstantially horizontal axis, and with a plurality of slot-like exhaust openings 31. Openings 31 are located in the rounded upper part of casting 34 so that the air discharged therethrough will be directed away from the surface onl which the device is supported.

From the foregoing. vit will be seen that the casing of the vacuum cleaner unit includes the main casing member II, the front cover I2, and the end-piece 34, and that both the front cover and the end-piece form a portion of the exterior of the casing.

Secured within opening 36 in casing 34 is a. cylindrical member 38. which..if desired, may be made of metal or Bakelite. Member 38 is provided with a cylindrical bore 39 of uniform diameter and with one or more grooves 40 extending from the inner end of the member to an intermediate point thereof. Cylindrical member 38 is provided with one or more ports 4I towards its inner end, and a.va1ve member 42 is reciprocally mounted within bore 39. Valve member 42 is provided with projections 43 which engage within grooves 40 to prevent rotation of the valve member. The valve member 42 is further provided with a plurality of air deflecting vanes 44 across the outer end. A conical spring 45 is disposed between the valve member and a ring 46 clamped between the end of y member 38 and a partition 41, the spring tending to hold the valve member in the position shown in Figs. 1, 3 and 4.

Partition 41 is secured to casting 34 and includes a substantially horizontal wall 48 and a substantially vertical Wall 49 which serve to partition oif a space 50 from the rest of the lter compartment 26. Exhaust openings 31 and ports 4I communicate with this space 50. Wall 49 is formed with a circular opening 5I communicating with the interior of member 38.

A plate 53 is carried by bulkhead 23 and is formed with an outer circular flange 54. Reference character 55 designates generally a filter' which includes a solid circular plate 56 and an annular plate 51. Plates 56 and 51 are held in spaced relationship by means of a. perforated cylinder 58. Filter cloth 59 is disposed between plates 56 and 51. The central opening in annular plate 51 fits around a cylindrical projection 60 formed by wall 49, whereby the filter 55 is positioned between wall 49 and plate 53.

'I'he operation of the above described device is as follows:

With the hose I5 connected to front cover I2, as shown in Fig. 1, the device is in condition for cleaning. Rotation of fain 28 by means of motor 21 causes air to be drawn in through nozzle I6, handle I1, hose I5, and coupling I4 to the interior of dust bag 20. y Here any entrained dust is deposited, and the air passes through the material of the dust bag and through the central opening in bulkhead 22 to the fan; 'Air discharged from the fan passes through and around the motor 21 and through the opening in bulk head 23 to the lter compartment. Here the air ows in the direction indicated by the arrows, which is radially outward around the edge of plate 53 and thence inwardly through the iiltercloth 59 and the perforated cylinder 58 to the interior of member 38.- A portion of the air passes straight through member 38 to the atmosphere, being deflected upwardly as it leaves the member by vanes 44. The remainder of the air passes through ports -4I to space 50 and thence through openings 31y to the atmosphere. It will be noted that all of the air thus discharged is directed away from the supporting surface. Furthermore, the aggregate area of the openings 31 and the openings between vanes 44 is sumciently great so that but a small baclepressureD If it is desired to employ'the device for blowing purposes, coupling I4 is removed from inlet opening I3 and is attached tothe exhaust opening formed by member 38, as is shown inA Fig. 6. When the coupling I4 is secured within, member 38, the end ofthe coupling displaces.

valve member 4I to the left, as viewed Vin the gures,ithereby compressing spring 45. In this position, vthe valve member covers the ports 4I, thereby cutting oiilr the flow of air through these ports to 'space 50 and hence, prevents exhaust of air through openings 31. Consequently, all ofthe air is forced to pass into hos'e I5.

Springy 45, being under compression, tends to displace coupling I4 to they right, as viewed in Fig. 6, but the coupling is positively secured. in member 38 by the balls. I4a engaging an annular recess formed in the member. 'I'he construction of this coupling is described in detail in the co-pending application of Lars Ell, Serial No.

force in this direction does not tend to release the balls from the groove, but tends to wedge them more tightly therein.

If it is desired to clean or replace filter 55, screws 35 are removed, thus releasing casting 34 from the main casing member This filter may then be removed through the opening which is normally closed by casting 34 and may be cleaned or replaced by a new one.

In the embodiment shown in Figs. 8 through 11, casting 34 is secured to the main casing member by means of a single bolt 65. This bolt is rotatably mounted in an arm which extends across the inner open end of cylindrical member 38 and is secured to the cylindrical member by means of screws 81. Bolt 85 is provided with spaced collars 88 and 89 which prevent longitudinal movement of the bolt with respect to arm 66 and hence, with respect to meinber 38 and casting 34. The inner end of bolt 65 is threaded, as is shown at 18, and is adapted to engage a threaded sleeve 1| secured to an arm 12 which is supported on member 13 forming a part of the seal 3| in the bulkhead 23. 'I'he other end of bolt 85 is provided with a preferably knurled head 14, the outer end of which is substantially ush with the outer edges of vanes 44. Spring 45 is disposed between valve member 42 and a washer 15 which surrounds bolt 65 and bears against arm 88. Plate 56 of filter 55 is formed with a small central opening within which sleeve 1| ts snugly. The plate bears against a sleeve 18 which surrounds sleeve 1| and is consequently of greater diameter than the opening in plate' 58.

The operation of this embodiment is the same as that described in connection with Figs. 1 through 7 insofar as the flow of air is concerned. With the parts in the position shown in Fig. 8 air is exhausted through both the exhaust opening 31 and through the opening in the end 'of member 38 in the same manner as described in connection with Fig. 4. When the hose is connected within member 38,' as is shown in Fig. 11, valve member 42 is moved tothe left so as to cover ports 4| and the entire ow of air is through member 38 and into the hose in the same manner as described in connection with Fig. 6. The hose coupling shown in Fig. 11 is described in detail in my co-pending application, Serial No. 61,473, filed January 30, 1938, Patent No. 2,102,802, issued December 21, 1937, and includes catch member |4b which engages in an annular groove, thus positively resisting the force of spring 45.

When it is desired to remove the filter 55, valve member 42 is pressed inwardly by the lingers until knurled head 14 is exposed suiiiciently to the grasp by the ngers. Thereupon, it is turned in the proper direction to unscrew bolt 85 from sleeve 1| and when this has been accomplished, casting 34 is released from the main part of the casing and may be removed therefrom. Filter 55 may then be removed and cleaned or replaced by a new one and the casting secured in place again by screwing the end of bolt 85 into sleeve 1|. As bolt 85 is tightened, it draws the edges of casting 34 against the edge of the opening formed in casing and the parts are thus held together in substantially air-tight relationship. At the same time, the iilter 55 is secured in place between wall 49 and sleeve 18 and the heads of bolts 19 which secure member 13 to bulkhead 23.

The embodiment shown in Fig. 12 differs from adapted to receive the end of sleeve 1|.

that described in connection with Figs. 8 through 11 principally in the fact that sleeve 1| is extended to adjacent the inner end of member 38, wherefore bolt 85 may be that much shorter. Arm 88, in which bolt 85 is journaled, is formed with a cylindrical part 88 having a flared open end Bolt 85 is formed with a collar 89 disposed between arm 88 and washer 15. The force required to hold casting 34 to casing member is exerted by the collar 89 against arm 88, while the only force between the collar and the washer 15 is that required to prevent the bolt dropping out when it is unscrewed from sleeve 1|, and the force exerted by spring 45 against the washer is sufiicient for this purpose.

The device shown in Fig. 12 has the advantage over that shown in Figs. 8 through 11, that it is somewhat easier to engage the threaded end of the shorter bolt with the sleeve 1| than it is to engage the threaded end of the longer bolt.. The

operation of the two devices is otherwise the same and the description thereof need not be repeated.

In the embodiment shown in Figs. 13 through 15, the bolt 85 for securing the end-piece 34 in place engages a threaded member 85 rigidly secured to a pivoted arm 88. This arm is rigidly secured, as by welding, to a member 81 having a cylindrical bore which receives a pin 88. Pin 88 is supported in a U-shaped member 89 which may be welded to the bottom of casing Member 81 is formed with a recess 90 containing a spring pressed ball 9|, which engages within a recess 92 formed in member 89 when the ball is brought into alignment with the recess. The length of arm 88 is less than one-half the width of casing so that it may be pivoted to a substantially horizontal position, as is shown in dash and dot lines in Fig. 14. v

The free end of arm 88 is formed with a recess adapted to 'receivev a projection 93 formed on a disc 94. Projection 93 may be the head of a rivet which extends through the disc and secures thereto the central part of spring member 95. The ends of spring 95 are secured to a ring 98. Ring 98 is formed with a flange 91 which retains in place a ring 98, which is adapted to be received and supported within ring 3|. A piece of lter cloth 99 is formed with a circular center opening and the edge of the cloth around this opening is clamped between rings 91 and 98. Filter cloth 99 has the shape shown in Fig. 13 and may consist of two pieces of cloth sewed together along the line |80. This cloth is retained between -spring 95 and disc 34.

In this embodiment the cylindrical member |8l, Within which member 42 is mounted, is shown as a stamping, but it performs the same function as does member 38 in the preceding embodiments. l

With the parts assembled as shown in Fig. 13, air discharged through the opening in bulkhead 23 is forced to pass through the filter 99. The air flow tends to distend the filter. The air after having passed through the filter' enters member End piece 34 may be removed from the main part of the casing Il, by unscrewing biolt 65.

v.To do this, valve member 42 is` forced inwardly so as to uncover the knurled head 'i4 on the bolt in orderthat it may be gripped with the fingers. When bolt 65 is released from the arm 86, the end piece is free to be removed.

If it is desired to renew the filter, arm 86 is pivoted in either direction to a horizontal po-sition, spring 95 being deformed slightly so as to permit rivet 93 to be disengaged from the opening in the end of the arm. With the arm 86 out of the way, ring 98 may be removed from within ring 3| and the filter as a whole removed through the opening normally closed by end-pieceA 34. A new filter may then be inserted `and the arm 86 pivoted to a vertical position, where it is retained by the engagement of the spring pressed ball 9| with the opening 92. In this position the arm engages rivet 93 and holds the filter in place and the screw threaded member 85 is in alignment with bolt 65 when the endlpiece 34 is put in place, and the bolt may be readily engaged with member 85 to hold the end piece in position.

It will thus be seen that I have provided a vacuum cleaner unit having a plurality of exhaust openings available for the exhaust of air while the cleaner is being used for suction purposes and that means are provided for connecting a hose to one of these openings and at the same time cutting oi iiow of air through the remaining openings so that all of the air passes into the hose. Furthermore, all of the exhaust openings are so arranged that air discharged therethrough is directed upwardly and away from the supporting surface. In the embodiments shown in Figs. 8 through 15, a single member is provided for securing the end-piece, in which the exhaust openings are formed and` which closes a filter chamber, to the remainder of the casing. This means is normally practically concealed from view and yet is readily accessible when it is desired to remove the end-piece.

While I have described several more or less specic embodiments of my invention, it is to be understood that this has been done for purposes of illustration only and that the scope is to be limited only by the appended claims viewed in the light of the prior art. I f

What I claim is:

1. In a vacuum cleaner, a casing having an exhaust opening, an air conduit connectible to said opening, air deflecting means for guiding flow of air through said opening when said conduit is disconnected, said deecting means being inwardly displaceable from a position substantially flush with the exterior of said casing by the oonnecting of said air conduit, and means for producing iiow of air through said casing and said opening.

2. In a vacuum cleaner, a casing having an exhaust opening, an air conduit connectible to said opening, air defiecting means movably mounted in said opening for guiding iiow 4of air through said opening when said conduit is disconnected, said deiiecting means being inwardly displaceable from a position substantially iiushr with exterior of said casing by the connecting of said air conduit, resilient means resisting displacement of said deiiecting meansand forcing the latter against said conduit, and means for positively locking said conduit in said opening.

3. In a vacuum cleaner, a casing having an inlet opening and a plurality of exhaust openings,

means for producing flow of air through said casing, a hollow member secured at one end to said casing and extending inwardly from one of said exhaust openings, the other end of said hollow member being arranged to receive all of the air exhausted from said means, said hollow member being formed with a port communicating with the other of said exhaust openings, and a cylindrical member reciprocably mounted in said hollow member for selectively closing and opening said port.

4. In a vacuum cleaner, a casing having an inlet opening and a plurality of exhaust openings, means for producing ow of air through said casing, a hollow member secured at one end to said casing and extending inwardly from one of said exhaust openings, the other end of said hollow member being arranged to receive all of the air exhausted from said means, said hollow member being formed with a port communicating with the other of said exhaust openings, a sleeve valve reciprocably mounted in said hollow member for closing and opening said port, and an air conduit connectible to said one of said exhaust openings, said sleeve valve being moved .to close said port by the connecting of said conduit.

5. In a vacuum cleaner, a casing adapted to be supported on a horizontal surface and having an inlet opening and a plurality of exhaust openings, means for producing owof air through said casing, one of said exhaust openings being adapted to be connected to an air conduit, valve means operable by the connecting of said conduit to sai-d one of said exhaust openings for cutting off iiow of air through the other of said exhaust openings, and means carried by said valve means and disposed across said one of said exhaust openings for deecting air away from said surface. v

6. In a vacuum cleaner, a casing having an inlet opening and a plurality of exhaust openings, means for producing ow of air through said casing, a hollow member secured at one end to said casing and extending inwardly from one of said exhaust openings, the other end of said hollow member being arranged to receive all of the air exhausted from said means, said hollow member being formed with a port communicating with the other of said exhaust openings, a valve member reciprocably mounted in said hollow member for selectively closing and opening said port, and vanes carried by said valve member for deiiecting air passing through said one of said exhaust openings.

7. In a vacuum cleaner, a casing adapted to be supported on a horizontal surface and formed with an inlet opening, one end of said casing having a portion inclined to the horizontal and formed with a plurality of exhaust openings therein, means for producing iiow of air through said casing, one of said exhaust openings being adapted to receive an air conduit, the remainder of said exhaust openings being located entirely in a portion of said end which is inclined away from said horizontal surface whereby air discharged therethrough is directed upwardly and away from said surface, valve means operative by connection of said air conduit for preventing iiow of air through said remainder of said openings, and means for deecting air discharged through said one of 'said openings upwardly and away from said surface.

8. In a vacuum cleaner, a casing adapted to be supported on a horizontal surface and formed with an inlet opening, one end of said casing-- being rounded and formed with a plurality of exhaust openings therein, means for producing ow of air through said casing, one of said exhaust openings being adapted to receive an air conduit, the remainder of said exhaust openings being located entirely in a portion of said end which is inclined away from said horizontal surface whereby air discharged therethrough is directed upwardly and away from said surface, a valve member reciprocably mounted in said one of said openings and operative by connection of said air conduit to prevent ow of air through said remainder of said openings, and means carried by said valve member for deecting air discharged through said one of said openings upwardly and away from said surface when said air conduit is disconnected.

9. In a vacuum cleaner, a casing having an air inlet, a fan in said casing for inducing ow of air through said inlet, a hollow member extending inwardly from an exhaust opening formed in said casing, means for conveying all ci the air discharged from said fan to said hollow member, said casing being formed with additional exhaust openings and said hollow member being formed with a port communicating with said additional exhaust openings, and valve means for closing said port.

l0. In a vacuum cleaner, a casing having an air inlet, a fan in said casing for inducing ow of air through said inlet, a hollow member extending inwardly from an exhaust opening formed in said casing, means for conveying all of the air discharged from said fan to said hollow. member, said casing being formed with additional exhaust openings and said hollow member being formed with a port communicating with said additional exhaust openings, an air conduit adapted to be connected to the first mentioned exhaust opening, and valve means operable by connecting said air conduit for closing said port.

1l. In a vacuum cleaner, a casing adapted to be supported on a horizontal surface and formed with an air inlet, a fan in said casing for inducing ow of air through said inlet, a hollow member extending inwardly from an exhaust opening formed in said casing, means for conveying all of the air discharged from said fan to said hollow member, said casing being formed with additional exhaust openings so positioned as to direct air ilowing therethrough away from said surface, said hollow member being formed with a port communicating with said additional exhaust openings, valve means for selectively closing said port, and means for directing air flowing through the rst mentioned exhaust opening away from said surface.

12. In a vacuum cleaner, a casing including a main member and an end-piece for closing one end of said main member, said end-piece forming a part of the exterior of said casing and having an exhaust opening, movable air deecting means for guiding flow of air through said opening, means within said opening for removably securing said end-piece to said main member, said securing means terminating substantially ush with said deecting means when the latter is in normal position, said deilecting means being movable to render said securing means accessible, and means for producing ow of air through said casing and said opening.

13. In a vacuum cleaner, a casing including a main member and an end-piece for closing one end of said main member, said end-piece forming a part of the exterior of said casing and having a plurality of exhaust openings therein, an air conduit adapted to be connected to one-of said openings, valve means operable by the connection of said conduit to out oi flow ,through the remainder of said openings, means disposed within said one of said exhaust openings and within said valve means for securing said end-piece to said main member, and means for circulating air through said casing.

14. In a vacuum cleaner, a casing including a main member and an end-piece for closing one end of said main member, said end-piece forming a part of the exterior of said casing and having a plurality of exhaust openings therein, an air conduit adapted to be connected to one of said openings, air derlecting means for guiding ilow of air through one of Said openings, valve means operable by the connection of said conduit to cut oi flow through the remainder of said openings, lmeans disposed within said one of said exhaust openings and within said valve means and extending through said air deilecting means for securing said end-piece to said main member, and means for circulating air through said casing.

l5. In a vacuum cleaner, a casing including a main member and an end-piece for closing one end of said main member, said end-piece forming a part of the exterior of said casing and having an exhaust opening, movable air deilecting means in said opening normally substantially ilush with the exterior of said casing for guiding flow of air through said opening, means Within said opening for removably securing said endpiece to said main member, said securing means terminating substantially flush with said deecting means when the latter is in normal position, and an air conduit connectible within said opening, said deflecting means being movable by the connecting of said conduit and being movable to render said securing means accessible.

16. In a vacuum cleaner, a casing including a main member and an end-piece for closing one end of saidmain member, said end-piece forming a part of the exterior of said casing and having a plurality of exhaust openings, movable air deflecting means in one of said openings and normally substantially ilush with the exterior of said casing, means within said one of said openings for removably securing said end-piece to i said main member, said securing means terminating substantially flush with said deecting means when the latter is in normal position, an air conduit connectible to said one of said openings, said deflecting means being movable by the connecting of said conduit and being movable to render said securing means accessible, and valve means operative by the movement of said deflecting means from normal position for cutting orf rlow of air through the other of said exhaust openings.

GUSTAF EINAR LOFGREN. 

